The S&P has been near its record high for several weeks, despite the still sluggish performance of the US economy. This means it finishes the quarter 10% higher than its level at the beginning of the year and more than double its low point during the financial crisis.

Bruce McCain, chief investment strategist at Key Private Bank in Cleveland said that the new closing high "is a very appropriate punctuation for a great quarter that saw a lot of last year's anxieties recede."

However, Michael Mullaney, chief investment officer at Fiduciary Trust in Boston warned "we don't know how long we'll be at these levels."